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11.
基于非线性网状创新模型提出的“三螺旋场”和“三螺旋循环”概念进一步推进了三螺旋创新模式的理论研究。三螺旋场概念旨在解释在大学、产业和政府三股螺旋之间存在的相对独立和彼此作用的本质,说明三螺旋的生成原理、静态表现和动态演化特征。三螺旋的生成原理在于创新过程的非线性本质和多主体特征,静态表现为“内核外场模型”,而动态演化过程则在于纵向进化和横向循环。发生在三股螺旋之间的三螺旋循环揭示了在大学、产业和政府之间以人员、信息和产品流动为特征的相互作用和运行机制。 相似文献
12.
曲流河、辫状河、网状河和若干三角洲的沉积模式目前已成为对比和解释古河流岩石层序的标准框架。但是,近来的野外资料和钻井资料证明,应该把末端扇模式加入上述沉积模式表中。末端扇的作用、地貌、有关的沉积物及沉积学特征相比河流体系及三角洲体系差距较大。通过大量的岩芯观察和描述,结合测井资料、区域地质资料及各项分析鉴定资料等进行综合分析,对东濮凹陷濮城油田沙二上亚段1砂组的沉积特征与沉积相进行了较全面的分析,认为该地区主要为末端扇沉积体系,在对末端扇的岩性、沉积相序、沉积微相特征分析的基础上,研究了末端扇的识别标志并建立了末端扇的沉积模式。 相似文献
13.
李强 《北京工商大学学报(社会科学版)》2008,23(1):82-86
我国股指期货推出的法律环境面临诸多不确定因素,一方面,《证券法》、新《期货交易管理条例》、《关于审理期货纠纷案件若干问题的规定》、《刑法》和新《破产法》、《中国金融期货交易所交易规则》的颁布和修订,为强化市场监管提供了强有力的法律依据;另一方面,现有法律体系在交易所规则的效力、会计制度、税收制度、净额结算、交易所的性质、透支交易、交易信息的送达、期货公司的举证责任、涉外期货等方面规定不明确,应对相关法律进行修改、梳理和完善,并在刑法典中增加虚假陈述罪、非法经营期货业务罪、泄漏内幕信息罪和挪用期货保证金罪等内容。 相似文献
14.
John S. J. HSU 《Revue canadienne de statistique》1995,23(4):399-410
This paper presents a new Laplacian approximation to the posterior density of η = g(θ). It has a simpler analytical form than that described by Leonard et al. (1989). The approximation derived by Leonard et al. requires a conditional information matrix Rη to be positive definite for every fixed η. However, in many cases, not all Rη are positive definite. In such cases, the computations of their approximations fail, since the approximation cannot be normalized. However, the new approximation may be modified so that the corresponding conditional information matrix can be made positive definite for every fixed η. In addition, a Bayesian procedure for contingency-table model checking is provided. An example of cross-classification between the educational level of a wife and fertility-planning status of couples is used for explanation. Various Laplacian approximations are computed and compared in this example and in an example of public school expenditures in the context of Bayesian analysis of the multiparameter Fisher-Behrens problem. 相似文献
15.
The labor quality index (LQI) not only serves as an important reference for monitoring the progress of the sustainable development
of a country, but it can also serve as an important parameter for economic analysis. To compile such an index for Taiwan,
we conducted two large-scale surveys of 1000 major enterprises and 844 union leaders, respectively, to determine the appropriate
weights for each key factor. We also searched for all the relevant statistics that were used to calculate the weighted sum
of the 25 sub-indexes, in order to compile a LQI for Taiwan’s manufacturing industries covering the period from 1990-2000.
Our calculations show that this LQI rose from 80.2 in 1990 to 117.5 in 2000, which reflected an impressive 37.3% increase
in just one decade. This rate of growth has, however, been slowing down since 1997. Our results indicate that the LQI provides
a valuable indicator for monitoring the enhancement of labor quality in this society. 相似文献
16.
在分析政府形象效能评价系统和信息置信度的基础上,建立了基于信度函数的政府形象评价模型。运用该函数建模分析了政府形象评估中的理念识别系统、行为识别系统、视觉识别系统、环境识别系统以及个人识别系统等五大不确定性评价问题。经过理论分析,该函数对政府形象的评估有较大的参考价值。此外,该函数也可以用于对其他类似复杂性系统的效能评估,具有普遍适用性。 相似文献
17.
We used two statistical methods to identify prognostic factors: a log-linear model (logistic and COX regression, based on the notions of linearity and multiplicative relative risk), and the CORICO method (ICOnography of CORrelations) based on the geometric significance of the correlation coefficient. We applied the methods to two different situations (a "case-control study' and a "historical cohort'). We show that the geometric exploratory tool is particularly suited to the analysis of small samples with a large number of variables. It could save time when setting up new study protocols. In this instance, the geometric approach highlighted, without preconceived ideas, the potential role of multihormonality in the course of pituitary adenoma and the unexpected influence of the date of tumour excision on the risk attached to haemorrhage. 相似文献
18.
Jan C. H. van Eijkeren 《Risk analysis》2002,22(1):159-173
A mechanistic model is presented describing the clearance of a compound in a precision-cut liver slice that is incubated in a culture medium. The problem of estimating metabolic rate constants in PBPK models from liver slice experiments is discussed using identifiability analysis. From the identifiability problem analysis, it appears that in addition to the clearance, the compound's free fraction in the slice and the diffusion rate of the exchange of the compound between culture medium and liver slice should be identified. In addition, knowledge of the culture medium volume, the slice volume, the compound's free fraction, and octanol-water-based partition between medium and slice is presupposed. The formal solution for identification is discussed from the perspective of experimental practice. A formally necessary condition for identification is the sampling of parent compound in liver slice or culture medium. However, due to experimental limitations and errors, sampling the parent compound in the slice together with additional sampling of metabolite pooled from the medium and the slice is required for identification in practice. Moreover, it appears that identification results are unreliable when the value of the intrinsic clearance exceeds the value of the diffusion coefficient, a condition to be verified a posteriori. 相似文献
19.
This study examines housing quality among three groups of single-parent women: white, African-American, and Hispanic. Three
indicators of housing quality—crowding, affordability, and satisfaction—are used to discover the extent to which these groups
experience housing problems. This study also explores differences and similarities in the factors that precipitate problems
in housing quality for these three groups of single parents. Findings suggest important differences and similarities in the
nature of housing quality problems among white, African-American, and Hispanic single-parent women. The specified variables
explained about 20% of the variance in crowding, housing affordability, and housing satisfaction. On measures of objective
and subjective housing quality, white single mothers are better housed than their African-American or Hispanic counterparts.
Hispanic single mothers have the largest housing cost burden and average more persons per household than the other groups.
African-Americans are twice as likely as either group to live in low-quality housing and reported the lowest average satisfaction
with their housing.
Her research interests include housing and neighborhood assessment and women and public policy issues. She has recently published
articles inUrban Affairs Quarterly andHousing and Society on housing and neighborhood assessment criteria among black urban households and the housing cost burden of various groups
of female-headed households. She received her Ph.D. from Ohio State University.
Her research interests include the housing adjustment behavior of women and public policy. She has recently completed her
thesis on the role of noncustodial parents in determining the quality of life of their children. She is also the recipient
of the Tessie Agan Award for research excellence from the American Association of Housing Educators for a paper titled “Unterstanding
Constraints and Residential Satisfaction among Low-Income Single-Parent Families.” 相似文献
20.
Projecting losses associated with hurricanes is a complex and difficult undertaking that is wrought with uncertainties. Hurricane Charley, which struck southwest Florida on August 13, 2004, illustrates the uncertainty of forecasting damages from these storms. Due to shifts in the track and the rapid intensification of the storm, real-time estimates grew from 2 to 3 billion dollars in losses late on August 12 to a peak of 50 billion dollars for a brief time as the storm appeared to be headed for the Tampa Bay area. The storm hit the resort areas of Charlotte Harbor near Punta Gorda and then went on to Orlando in the central part of the state, with early poststorm estimates converging on a damage estimate in the 28 to 31 billion dollars range. Comparable damage to central Florida had not been seen since Hurricane Donna in 1960. The Florida Commission on Hurricane Loss Projection Methodology (FCHLPM) has recognized the role of computer models in projecting losses from hurricanes. The FCHLPM established a professional team to perform onsite (confidential) audits of computer models developed by several different companies in the United States that seek to have their models approved for use in insurance rate filings in Florida. The team's members represent the fields of actuarial science, computer science, meteorology, statistics, and wind and structural engineering. An important part of the auditing process requires uncertainty and sensitivity analyses to be performed with the applicant's proprietary model. To influence future such analyses, an uncertainty and sensitivity analysis has been completed for loss projections arising from use of a Holland B parameter hurricane wind field model. Uncertainty analysis quantifies the expected percentage reduction in the uncertainty of wind speed and loss that is attributable to each of the input variables. 相似文献